Clamp for electric welding-machines.



G. E. BARSTOW. cLAMr FOR ELECTRIC WELDING MACHINES.

APPLICATION FILED MAY 11, 1 907.

Patented Mar. 29

6 SHEETS-SHEET 1.

| I y In .L-L

INVENTOR 607" e igazsf uz J By v I ATTORNEYS WITNESSES:

G. E. BARSTOW.

CLAMP FOB ELECTRIC WELDING MACHINES.

. APPLICATION FILED MAY 11, 1907. 95 3,579.

5 SHEETS-SHEET 2.

Patented Mar. .29, 1910.

G. E. BARSTOW. CLAMP FOR ELECTRIC WELDING MACHINES.

APPLICATION FILED MAY 11, 1907. 95 3,579. Patented Mar. 29, 1910.

5 SHEETS-SHEET 3.

WITNESSES. a a Q 2 I? INVNTOR 6'02 dfirrrsfow WWW I 15 ATTORNEYS G. E. BARSTOW.

CLAMP FOR ELECTRIC WELDING MACHINES.

APPLICATION IILED MAY 11, 1907.

Patented Mar. 29, 1910.

5 SHEETS-SHEET INVENTOH jageaflar l ow ATTORNEYS.

G. E. BARSTOW.

CLAMP FOR ELECTRIC WELDING MACHINES.

APPLICATION FILED MAY 11, 1907.

M Patented Mar. 29, 1910.

UNITED s rn ns PATENT on-Fion GEORGE BARSTOW, OF LYNN, MASSACHUSETTS, ASSIGNOR 'IO THOMSON ELECTRIC WELDING COMPANY, OF LYNN, MASSACHUSETTS, A CORPORATION OF MAINE.

CLAMP FOR ELECTRIC WELDING-MACHINES.

Specification of Letters Patent.

Patented Mar. 29, 19161.

Application filed May 11, 1907. Serial No. 373,030.

-To all whom it may camera:

Be it known that I, GEORGE E. BARsToW, a citizen of the United States, and a resident of Lynn, in the county of Essex and State of Massachusetts, have invented certain new cient and rapidly operable mechanism capa ble of applyinglieavyvclamping pressure. 1

In'a'n electrie'metal working apparatus, it is frequently necessary when the 'work 1s heavy, to apply avery heavyclamping pres sure-to the workin order to preventdisplacement thereof in the 'wOrk-holdin-g-flevices. This is especially necessaryin the operatlon' of welding heavy pieces of-metal' in which operation it is necessary to apply very heavy pressure to the work in a line which would tend to displace the work in the clamping mechanism.

Generally speaking, my invention consists of a clamping mechanism,- having a piv-= otally mounted member combined with an eccentric forming the pivotal mounting for said member whereby afterthe clamping jaw has been engaged with the work by the turning ef said member on its pivot, the

operation of the eccentric will-apply the final heavy pressure to securely fix'the work.

ousways. Thus,'for instance, the lever by the turning of which the clamping'jaw is fas-' tened in engagement with'the work may have its pivotal" mounting upon the eccentric" so that after said fastening lever has been operated, the turning of the eccentric by an operating arm or other deviceconnected thereto will apply the increased pressure. ()r the clamping mechanism may have its clamping jaw pivotaily mounted and the eccentric may serveas the pivotal support for.

said pivotally mounted clamping j aw so that after the jaw hasbeen-turned on its pivot and engaged with the work and fastened by any proper fastening device, the subsequent turning oft-he eccentric by any proper operating device will apply the heavy orfinalv pressure. Also- In carrying "out my invention, the clamping jaw may be either pivot-' ally or slidablymounted as will hereinafter :embodying my invention.

ism are indicated at 2, 2.

more clearly appear from the subjoined description taken in connection with the accompanying drawings.

My invention permits not only the application of a very heavy pressure to the work, but enables the operatorto manipulate the clamping mechanism in an expeditious 1115111 ner so that, although the work is-large and the clamping pressure heavy, no time will -be wasted in the insertion and removal of the work from its position in the work holder;

My invention consists further in the special details of construction and combinations of parts hereinaftermore particularly described and then specified in the claims.

In the accompanying drawings: Figure l is an end elevation of one form of apparatus Fig'J-Q is'a similar View taken from the reverse end. Fig: 3 is a vertical longitudinal section through a portion of the device carrying the removable clamp jaw taken on the line-A, A, Fig. 1.

Fig. 4: is a-pl'an ofthefapparatus, a portion being shown in horizontal section. Fig. 5

is aside elevation and partial section of the apparatus, the section. being taken vertically through one of the -fastenin levers and its eccentric-mounting. Fig. 6 1s a vertical section on the line B, B, Fig. '1. Fig. 7 is a detached side view of the eccentric shaft. Fig.

8 is an end view of said shaft with the fastening lever mounted on the eccentric there- My invention may be carried out in variis a side elevation of the lever with the attached spring dog, Fig. 11 is a side elevation of the -pivotallymounted clamping jaw and illustrates a modification of my invention in which the eccentric is. applied to the pivotahsupport of the jaw. "Fig. 12 is a plan and horizontal section illustrating the application of my invention to a work clamping mechanism in which -.the-clamping jaws are-slidably n'iounted. "Fig. 18 is an end elevation of the apparatus shown in Fig. 12.

Referring to Figs. 1 to 5, the usual platens or supports for the work clamping mechan- These platens work in the usual way upon any proper guides on the frame or table of the machine and areconnected to a source of electric en supper )11 the pivot mounted ards '6 rising from a casting 7 bolted to the platen or other support in the in standwhich is usual manner. The manner ct securing the clamping jaw on its le it supportand ad iusting' the surface oi to the work will be described later on.

8 is the lower or fixed aw and. 9 is a piece of work c the jaws 3 and 8. he lower w 8 is prelfe ahly, as illustrated in l ig. 6, c .chably secured to the side of a block 10, said block beii itself fastenedto the platen or other so ort. its usual in the art the jaw 8 is made some hard metal of good conducting quail such, for instance, as bronze and the hlsupport 10, to which it is attached made usually of copper.

13. is a fastening" lever for fastening the jaw down into engagement with the work for which purpose it may. he brought into, and

out of engagement with the jaw carrying.

lever 4- by means ofthe operating handle 12 serving to swing the portion 11 oi the clamping mechanism upon the pivotal support thereon ln Figs. 1 to 5, inclusive, 1 show present invention. as applied to this pivotecl portion of the clamping mechanism by using" an eccentric 13 as tne pivotal mounting for the lever l1.

1% is an eccentric shaft which is mounted in any proper manner, as, for instance, in earings 15 secured in bosses 16 projecting om a plate or casting 17 The latter is iastened in any proper manner to any suitable support as, for. instance, to the platen. Connected to the shalt oil the eccentric 14 is an operating arm or lever 18 whereby the shaft may be turned to operate the eccentric and thereby pull down the fastening lever 11 with its attachment engaging the jaw-carrying lever 4-. The pivotally mounted lever 11 of the clamping mechanism may engage lever 4: and secure the jaw carried thereby in engagement with the work bya device of any kind as may be found convenient. The device shown comprises a cam block 19 adapted to ride upon a cam block 20 mounted on the jaw carrying lever 4- in the manner commonly employed in the art. When. the pivoted fastening lever 11 swung back to position shown in Fig. 2., the jaw is freed and its supporting lever 4: may turned up to permit withdrawal of the work, but when the jaw is down upon the work and the lever 11 jitW with relation in. block 19, l

on the bloc. a

down upon the much he icL' or the Lite]? reinforced essure 18 secured by turin aw J 1 union a 1Q eccentric sl aft 14: by means of the operating arm 18. is already stated, the eccentric may be applied to any pivf at the fasteningmcchanisni .1 i have, in 11. shown the same as M to the otal 7 mounting of the clampin jaw by ui using the eccentric illustrated" in clotted l ass at 13' as the pivot for the yaw-carrying l.

The eccentric shaft Li would in tha ca be provided with an operating lever 1S I to 18 so that after the clamping been fasten en down upon the work my device as for instance. fastening is or 11 whether mounted eccentrically or not. the turning" of the ecceni by its opu'iting lever 18' will permit the application of the necessary heavy or i'eii forced pressure.

The jaw carrying lover l may be provided with a rcarwardly extending arm 21 carrying a weight 22 bymeans of which. will be raised from the work wh from the fastening device. The t cam block 19 is preferably, dctachaln cured to the fastening lever 11 by means of a pin on the hiock which may be driven into a socket in a lateral projection of the lever. in case of renewal, the cued cam block lflinay be Li men out of its socket in obvious manner. ccentric ope lever 18 is pi 'erably pm led with a catch com ising a spring actuated (it; which who-i the lever is turned position shown in free the ing mechanism from the action of the tric, will engage a notch at 2st the edge of a catch plate 35 which is to the side of one or" the l; suitable fixed support. lever will be held up or by forcible ,tiovement of the lever in a direction to car y its handle end downward, the catch will be .freed and the eccentric will be turned to apply the heavy or reinforced pressure The catch plate is shown ii. edge view Fig. 5 but is omitted from the sectional portion of the, figure at the right hand side thereof to avoid confusion.

A stop 26 projecting i im the plate the downward thrgw of the eccent crating lever .18 in up" 1g the in reinforced pressure s as to prevei... the passage of the eccentric r the high point in a manner to relieve the pressure.

The spring actuated dog 23 is mounted upon a rod 27 and works with said id in a bore formed in a pro cd or attached to the side of 1 g lever 18. A spring 29 surrounding the rod and working against the head constituting dog 23 serves to force the into engagement with the notch'24 and to keep the dog engaged with the edge of the catch plate 25.

The work clamping jaw 3 is, preferably, detachably secured to the lever 4 and is provided with means whereby it may be adjusted to bring the plane of its clamping face into proper relation to the plane of the work engaged thereby. For this purpose, the jaw is fastened against the side of the lever 4 by means of fastening screws or bolts after adjustment of position of. the jaw upon the lever by means of the several adjusting screws 31 which bear upon the upper side or edge of the clamp jaw and work in openings tapped vertically in the overhanging upper edge of the lever 4, as more clearly shown in Fig. 6. Each adjusting screw 31 is preferably operated by means of an arm 32 extending from a toothed hub or sleeve 33, the teeth of which engage a correspondingly notched sleeve 34 pinned or fastened to the screw shaft. The hub 33 is free to move longitudinally of the screw shaft to disengage its teeth from the notches in the sleeve 34 and to prevent detachment of sleeve 33 from the screw shaft the latter is provided with the head 35. By thisdevice the operating arms or levers 32 may be brought around to any position where they will be out of the way after the screw has been turned in adjusting the clamp jaw.

This device also aids the operator in turning the screw step by step by turning the lever 32 in the arc of a circle, whereas were the arm rigidly attached to the screw it would be necessary in any extended ad ustment to turn the lever through a whole circle.-

The clamping bolts or screws 30 work in vertically elongated slots or openings in the si e ofthe jaw carrying lever 4. In order that the jaw may rise automaticallywhen the adjusting screws are turned back and be retained in engagement with the ends of said screws, I provide plates 36 interposed between the jaw and the. face on lever 4 against which it is fastened by the clamping screws or bolts 30 and having .an opening through which the untapped portion of the bolt passes- The plate 36 is, lifted by the action of a spring 37 seated in a :socket in the top of the lever 4 and working against the head 38 of a rod 39 rising from the plate '36. To adjust the jaw, the screws 31 are adjusted as may be required to set the jaw in the proper position upon the lever 4. If the screws 31 he turned down the plates 36 will follow. the jaw and the clamping bolts 30, the springs 37 yielding in "such case. 'I f the screws are turned back, the springs 37 will raise the plates 36 with the bolts and attached jaw keeping the upper edge of the jaw engaged with the adjusting screws, After readjustment the setting of the bolts 30 will fix the jaw on the supporting lever 4 in the desired position.

In the operation of the apparatus for the insertion of a new piece of work the fastening lever 11 is turned to free the pivotally mounted jaw' and permit the jaw-carrylng lever to rise under the action of the weight 22 and leave the work freely exposed for removal and to permit the placing of a fresh piece of work upon its support. The clamping jaw is then brought down upon the work and the pivotally mounted member 11 of the clamping devices is turned up to position shown in Fig. 1 to fasten the jaw in engagement with the work. The eccentric op- 1 crating lever 18 which at such time is in position shown in Fig. 1, where it will be held sustained by the catch already described,is then forcibly turned down as far as it will go toward position indicated in Fig. 9, thus turning the eccentric forming the pivotal mounting of the member 11 and applying the reinforced or heavy pressure; or obviouslythe heavy or reinforced pressure may be applied or may be supplemented by operating the lever 18' in the proper direction provided'the lever 4 be a member of the clamping devices which is pivotally mounted on an eccentric. A handle 40 may be applied to the jaw-carrying lever 4 to assist in bringing. the same down upon the work and a stop 41 may be provided for limiting the backward movement of the fastening lever 11 when thrown to free the lever 4. Obviously the same devices may be used for the clanping devices carried by bothplatens 2 an 2 i 1 higs. 13 and 12 illustrate the application of my invention to a slidably mounted clamping jaw and clamping mechanism having a pivoted memberof the general construction illustrated in patents to A. F. RietzelNo. 766,288 dated Aug. 2nd, 1904, or No. 804,045, dated Nov. 7th, 1905. The fastening in this instance comprises a cam pro jection 15 extending from the hub of the fastening lever 11 and engaging a detachable plate 42 on the end of the slide which carries the clamp jaw 3. Lever 11 is pivotally mounted by its hub as better shown in Fig.12 on the eccentric portion of the eccentric shaft 14, s'aid shaft being provided, as already described, with an operating arm or'lever 18. A pin 43projecting from the hub or casting operates on the book 4 t extending from the slide toretract the jaw 3 and free the work 9. The opposite jaw 8 is mounted and adjusted as described in latout No. 766,288. The shaft for the eccentrio is suitably mounted in a bearing capable of adjustment to and from the work thereby permitting the eccentric to be adjusted so that it will act properly in case of variation of the size of the work. For this purpose the bearing 45 for the shaft 14 is mounted in a horizontal elongated opening in the casting 46 and said casting is provided with a set screw 47 which engages the hearing 4:5 and thereby ad usts the same with the shaft and eccentric in relation tethe cerns my present invention, the same in prin ciple as that shown in the other figures.

The pivotally mounted member 11 of the clamping devices having been operated to fasten the slidably mounted jaw 8 against the work, the lever 18 attached to the eccentric shaft is turned, thereby applying increased pressure to the jaw 3 by the action of the eccentric upon the pivotally mounted member 11. To free the work, the eccentric operating arm or lever 18 is turned back and then the pivotally mounted member 11 is turned to uncouple or free the fastening device.

I do not limit myself to pivotally mounting any particular member of the clamping mechanism for the work upon an eccentric, but prefer to apply the eccentric to the pivot of that member of the clamping mechanism which carries a fastening device movable into and out of position to set, hold or bring the clamping jaw into engagement with the work with an initial pressure which, by the operation of the eccentric, can be reinforced or supplemented to immovably clamp the work as already described. .7

What I claim as my invention is:

1. In an electric'metal working apparatus, the combination of work clamping devices having a pivotally mounted member adapted to engage the clamping jaw with the work by a turning movement upon its pivot, and an eccentric forming a pivotal point of support for said member, as and for the purpose described.

2. In an electric metal working apparatus,

the combination of work clamping inechan-v ism having a pivotally mounted member adapted to engage the clamping jaw with the work by a turning movement on its pivot, an eccentric forming the pivotal mounting therefor, and an eccentric shaft provided with an operating as and for the purpose described.

3. an electric metal working apparatus, the combination. of work clamping devices having a pivotal-1y mounted fastening device adapted to bring the clamping jaw in engagement with the work by a turning movement on its pivot, and an eccentric forming the pivotal mounting for said fastoning device.

4:. ltn an electric metal working apparatus, the combination of work clamping mechanism having a pivotally mounted fastening device adapted to fasten the clamping jaw in engagement with the work by turning on its pivot, an eccentric forming the pivotal mounting therefor and an eccentric shaft provided with an operating arm, as and for the purpose described.

5. In an electric metal working apparatus, thecombination of work clamping mechanism having a clamping jaw mounted on a pivoted support, a pivotally mounted fastening lever adapted to engage said support by a turning movement on its pivot to fasten said jaw in engagement with'the work, and an eccentric forming the pivotal mounting for said fastening lever.

6. In an electric metal working apparatus, the combination of a work clamping mechanism having a clamping jaw, a pivotally mounted support therefor and a pivotally mounted fastening device adapted to engage the support and fasten the jaw in engagement with the work, an eccentric forming the pivotal mounting for said fastening device and an eccentric shaft provided with an operating arm, as and for the purpose descrlbed.

7. In an electric metal Working apparatus, the combination of a clamping jaw, 21 support for the same, a fastening lever having a cam adapted to engage the support and fasten the jaw upon the work, an eccentric upon which said lever is pivoted, and an eccentric shaft provided with means for operating the same, as and for the purpose describe) 8. In an electric metal working apparatus, the combination of a clamping jaw, a pivoted support therefor, a pivoted-fastening lever provided with a lug or projection adapted to engage the pivoted support to fasten the jaw in engagement with the work and an eccentric forming a pivotal mounting for said fastening lever.

9. In an electric metal working apparatus, the combination of a pivotally mounted clamping jaw, an eccentric forming the pivotal mounting for the jaw and a shaft for said eccentric provided with an operating arm, as and for the purpose described.

Signed at Lynn in the county of Essex and State of Massachusetts this 17th day of a t-a a. n. 1907.

GEORGE E. BARSTOVV.

Witnesses:

ADA J. NIoHoLs, (3110. W. N. CHADWELL. 

